query_question: A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at230°C by rejecting its waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 65°C and leaves at 42°C. The inlet state of the compressor is 60 kPa and 234°C and the compressor is estimated to gain a net heat of 450 W from the surroundings. Determine the quality of the refrigerant at the evaporator inlet.<image 1>
options: ['q=0.28', 'q=0.38', 'q=0.48']
demo_question_list: An insulated piston-cylinder device contains 5 L of saturated liquid water at a constant pressure of 175 kPa. Water is stirred by a paddle wheel while a current of 8 A flows for 45 min through a resistor placed in the water. If one-half of the liquid is evaporated during this constant-pressure process and the paddle-wheel work amounts to 400 kJ, determine the voltage of the source. Also, show the process on a P-v diagram with respect to saturation lines. <image 1>
  A. 204 V
  B. 224 V
  C. 244 V
  
  Answer with the option's letter from the given choices directly. The tank of liquid in the figure P2.139 accelerates to the right with the fluid in rigid-body motion. Compute a_x in m/s^2. <image 1>
  A. 1.00 m/s2
  B. 1.50 m/s2
  C. 1.28 m/s^2
  
  Answer with the option's letter from the given choices directly. An ideal gas taken round the cycle ABCA as shown in PV diagram<image 1>.The work done during the cycle
  A. PV
  B. PV/2
  C. 2PV
  D. PV/3
  
  Answer with the option's letter from the given choices directly. The long pipe in Fig. 3.133 is filled with water at 20°C. When valve A is closed, p1 - p2 = 75 kPa. When the valve is open and water flows at 500 m^3/h, p_1 - p_2=160 kPa. What is the friction head loss between 1 and 2, in m, for the flowing condition? <image 1>
  A. 7.6 m
  B. 9.2 m
  C. 8.7 m
  
  Answer with the option's letter from the given choices directly.